Generally, in a modern communications system, transmit power control may be crucial to an overall performance of the communications system. Transmit power control may be able to reduce inter-cell interference in the communications system, as well as help communications devices (also commonly referred to as User Equipment (UE), mobiles, mobile stations, users, subscribers, terminals, and so on) achieve a required Signal to Interference plus Noise Ratio (SINR).
Consider, for example, a Third Generation Partnership Project (3GPP) Long Term Evolution (LTE) compliant communications system, wherein Orthogonal Frequency Division Multiple Access (OFDMA) is used as a basic access scheme for a downlink (DL) between an enhanced NodeB (eNB) (also commonly referred to as NodeB, base station, controller, communications controller, and so forth) and UEs served by the eNB. While, on the uplink (UL), Single Carrier FDMA (SC-FDMA) is used as a basic access scheme. SC-FDMA, which has better Peak to Average Power Ratio (PAPR) properties than OFDMA. The selection of SC-FDMA was made in part due to stricter power restrictions in UEs.
Typically, there are two different types of power control: open loop power control (OLPC) and closed loop power control (CLPC). In CLPC, a controller, such as in an eNB, may adjust the transmit power, for example, of UEs, based on feedback information. While, as its name suggests, in OLPC a communications device, such as a UE, may set its own transmit power level without any feedback from a controller. The two different types of power control may be used separately or in conjunction to control the transmit power level of communications devices in a communications system.